<?php
  class Core_Mail_Smtp{
	  /**
	   *  SMTP server port
	   *  @var int
	   */
	  public $SMTP_PORT = 25;
	
	  /**
	   *  SMTP reply line ending
	   *  @var string
	   */
	  public $CRLF = "\r\n";
	
	  /**
	   *  Sets whether debugging is turned on
	   *  @var bool
	   */
	  public $do_debug;       // the level of debug to perform
	
	  /**
	   *  Sets VERP use on/off (default is off)
	   *  @var bool
	   */
	  public $do_verp = false;
	
	  /////////////////////////////////////////////////
	  // PROPERTIES, PRIVATE AND PROTECTED
	  /////////////////////////////////////////////////
	
	  private $smtp_conn; // the socket to the server
	  private $error;     // error if any on the last call
	  private $helo_rply; // the reply the server sent to us for HELO
	
	  /**
	   * Initialize the class so that the data is in a known state.
	   * @access public
	   * @return void
	   */
	  public function __construct() {
	    $this->smtp_conn = 0;
	    $this->error = null;
	    $this->helo_rply = null;
	
	    $this->do_debug = 0;
	  }
	
	  /////////////////////////////////////////////////
	  // CONNECTION FUNCTIONS
	  /////////////////////////////////////////////////
	
	  /**
	   * Connect to the server specified on the port specified.
	   * If the port is not specified use the default SMTP_PORT.
	   * If tval is specified then a connection will try and be
	   * established with the server for that number of seconds.
	   * If tval is not specified the default is 30 seconds to
	   * try on the connection.
	   *
	   * SMTP CODE SUCCESS: 220
	   * SMTP CODE FAILURE: 421
	   * @access public
	   * @return bool
	   */
	  public function Connect($host, $port = 0, $tval = 30) {
	    // set the error val to null so there is no confusion
	    $this->error = null;
	
	    // make sure we are __not__ connected
	    if($this->connected()) {
	      // already connected, generate error
	      $this->error = array("error" => "Already connected to a server");
	      return false;
	    }
	
	    if(empty($port)) {
	      $port = $this->SMTP_PORT;
	    }
	
	    // connect to the smtp server
	    $this->smtp_conn = @fsockopen($host,    // the host of the server
	                                 $port,    // the port to use
	                                 $errno,   // error number if any
	                                 $errstr,  // error message if any
	                                 $tval);   // give up after ? secs
	    // verify we connected properly
	    if(empty($this->smtp_conn)) {
	      $this->error = array("error" => "Failed to connect to server",
	                           "errno" => $errno,
	                           "errstr" => $errstr);
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": $errstr ($errno)" . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	
	    // SMTP server can take longer to respond, give longer timeout for first read
	    // Windows does not have support for this timeout function
	    if(substr(PHP_OS, 0, 3) != "WIN")
	     socket_set_timeout($this->smtp_conn, $tval, 0);
	
	    // get any announcement
	    $announce = $this->get_lines();
	
	    if($this->do_debug >= 2) {
	      echo "SMTP -> FROM SERVER:" . $announce . $this->CRLF . '<br />';
	    }
	
	    return true;
	  }
	
	  /**
	   * Initiate a TLS communication with the server.
	   *
	   * SMTP CODE 220 Ready to start TLS
	   * SMTP CODE 501 Syntax error (no parameters allowed)
	   * SMTP CODE 454 TLS not available due to temporary reason
	   * @access public
	   * @return bool success
	   */
	  public function StartTLS() {
	    $this->error = null; # to avoid confusion
	
	    if(!$this->connected()) {
	      $this->error = array("error" => "Called StartTLS() without being connected");
	      return false;
	    }
	
	    fputs($this->smtp_conn,"STARTTLS" . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($this->do_debug >= 2) {
	      echo "SMTP -> FROM SERVER:" . $rply . $this->CRLF . '<br />';
	    }
	
	    if($code != 220) {
	      $this->error =
	         array("error"     => "STARTTLS not accepted from server",
	               "smtp_code" => $code,
	               "smtp_msg"  => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	
	    // Begin encrypted connection
	    if(!stream_socket_enable_crypto($this->smtp_conn, true, STREAM_CRYPTO_METHOD_TLS_CLIENT)) {
	      return false;
	    }
	
	    return true;
	  }
	
	  /**
	   * Performs SMTP authentication.  Must be run after running the
	   * Hello() method.  Returns true if successfully authenticated.
	   * @access public
	   * @return bool
	   */
	  public function Authenticate($username, $password) {
	    // Start authentication
	    fputs($this->smtp_conn,"AUTH LOGIN" . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($code != 334) {
	      $this->error =
	        array("error" => "AUTH not accepted from server",
	              "smtp_code" => $code,
	              "smtp_msg" => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	
	    // Send encoded username
	    fputs($this->smtp_conn, base64_encode($username) . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($code != 334) {
	      $this->error =
	        array("error" => "Username not accepted from server",
	              "smtp_code" => $code,
	              "smtp_msg" => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	
	    // Send encoded password
	    fputs($this->smtp_conn, base64_encode($password) . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($code != 235) {
	      $this->error =
	        array("error" => "Password not accepted from server",
	              "smtp_code" => $code,
	              "smtp_msg" => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	
	    return true;
	  }
	
	  /**
	   * Returns true if connected to a server otherwise false
	   * @access public
	   * @return bool
	   */
	  public function Connected() {
	    if(!empty($this->smtp_conn)) {
	      $sock_status = socket_get_status($this->smtp_conn);
	      if($sock_status["eof"]) {
	        // the socket is valid but we are not connected
	        if($this->do_debug >= 1) {
	            echo "SMTP -> NOTICE:" . $this->CRLF . "EOF caught while checking if connected";
	        }
	        $this->Close();
	        return false;
	      }
	      return true; // everything looks good
	    }
	    return false;
	  }
	
	  /**
	   * Closes the socket and cleans up the state of the class.
	   * It is not considered good to use this function without
	   * first trying to use QUIT.
	   * @access public
	   * @return void
	   */
	  public function Close() {
	    $this->error = null; // so there is no confusion
	    $this->helo_rply = null;
	    if(!empty($this->smtp_conn)) {
	      // close the connection and cleanup
	      fclose($this->smtp_conn);
	      $this->smtp_conn = 0;
	    }
	  }
	
	  /////////////////////////////////////////////////
	  // SMTP COMMANDS
	  /////////////////////////////////////////////////
	
	  /**
	   * Issues a data command and sends the msg_data to the server
	   * finializing the mail transaction. $msg_data is the message
	   * that is to be send with the headers. Each header needs to be
	   * on a single line followed by a <CRLF> with the message headers
	   * and the message body being seperated by and additional <CRLF>.
	   *
	   * Implements rfc 821: DATA <CRLF>
	   *
	   * SMTP CODE INTERMEDIATE: 354
	   *     [data]
	   *     <CRLF>.<CRLF>
	   *     SMTP CODE SUCCESS: 250
	   *     SMTP CODE FAILURE: 552,554,451,452
	   * SMTP CODE FAILURE: 451,554
	   * SMTP CODE ERROR  : 500,501,503,421
	   * @access public
	   * @return bool
	   */
	  public function Data($msg_data) {
	    $this->error = null; // so no confusion is caused
	
	    if(!$this->connected()) {
	      $this->error = array(
	              "error" => "Called Data() without being connected");
	      return false;
	    }
	
	    fputs($this->smtp_conn,"DATA" . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($this->do_debug >= 2) {
	      echo "SMTP -> FROM SERVER:" . $rply . $this->CRLF . '<br />';
	    }
	
	    if($code != 354) {
	      $this->error =
	        array("error" => "DATA command not accepted from server",
	              "smtp_code" => $code,
	              "smtp_msg" => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	
	    /* the server is ready to accept data!
	     * according to rfc 821 we should not send more than 1000
	     * including the CRLF
	     * characters on a single line so we will break the data up
	     * into lines by \r and/or \n then if needed we will break
	     * each of those into smaller lines to fit within the limit.
	     * in addition we will be looking for lines that start with
	     * a period '.' and append and additional period '.' to that
	     * line. NOTE: this does not count towards limit.
	     */
	
	    // normalize the line breaks so we know the explode works
	    $msg_data = str_replace("\r\n","\n",$msg_data);
	    $msg_data = str_replace("\r","\n",$msg_data);
	    $lines = explode("\n",$msg_data);
	
	    /* we need to find a good way to determine is headers are
	     * in the msg_data or if it is a straight msg body
	     * currently I am assuming rfc 822 definitions of msg headers
	     * and if the first field of the first line (':' sperated)
	     * does not contain a space then it _should_ be a header
	     * and we can process all lines before a blank "" line as
	     * headers.
	     */
	
	    $field = substr($lines[0],0,strpos($lines[0],":"));
	    $in_headers = false;
	    if(!empty($field) && !strstr($field," ")) {
	      $in_headers = true;
	    }
	
	    $max_line_length = 998; // used below; set here for ease in change
	
	    while(list(,$line) = @each($lines)) {
	      $lines_out = null;
	      if($line == "" && $in_headers) {
	        $in_headers = false;
	      }
	      // ok we need to break this line up into several smaller lines
	      while(strlen($line) > $max_line_length) {
	        $pos = strrpos(substr($line,0,$max_line_length)," ");
	
	        // Patch to fix DOS attack
	        if(!$pos) {
	          $pos = $max_line_length - 1;
	          $lines_out[] = substr($line,0,$pos);
	          $line = substr($line,$pos);
	        } else {
	          $lines_out[] = substr($line,0,$pos);
	          $line = substr($line,$pos + 1);
	        }
	
	        /* if processing headers add a LWSP-char to the front of new line
	         * rfc 822 on long msg headers
	         */
	        if($in_headers) {
	          $line = "\t" . $line;
	        }
	      }
	      $lines_out[] = $line;
	
	      // send the lines to the server
	      while(list(,$line_out) = @each($lines_out)) {
	        if(strlen($line_out) > 0)
	        {
	          if(substr($line_out, 0, 1) == ".") {
	            $line_out = "." . $line_out;
	          }
	        }
	        fputs($this->smtp_conn,$line_out . $this->CRLF);
	      }
	    }
	
	    // message data has been sent
	    fputs($this->smtp_conn, $this->CRLF . "." . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($this->do_debug >= 2) {
	      echo "SMTP -> FROM SERVER:" . $rply . $this->CRLF . '<br />';
	    }
	
	    if($code != 250) {
	      $this->error =
	        array("error" => "DATA not accepted from server",
	              "smtp_code" => $code,
	              "smtp_msg" => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	    return true;
	  }
	
	  /**
	   * Sends the HELO command to the smtp server.
	   * This makes sure that we and the server are in
	   * the same known state.
	   *
	   * Implements from rfc 821: HELO <SP> <domain> <CRLF>
	   *
	   * SMTP CODE SUCCESS: 250
	   * SMTP CODE ERROR  : 500, 501, 504, 421
	   * @access public
	   * @return bool
	   */
	  public function Hello($host = '') {
	    $this->error = null; // so no confusion is caused
	
	    if(!$this->connected()) {
	      $this->error = array(
	            "error" => "Called Hello() without being connected");
	      return false;
	    }
	
	    // if hostname for HELO was not specified send default
	    if(empty($host)) {
	      // determine appropriate default to send to server
	      $host = "localhost";
	    }
	
	    // Send extended hello first (RFC 2821)
	    if(!$this->SendHello("EHLO", $host)) {
	      if(!$this->SendHello("HELO", $host)) {
	        return false;
	      }
	    }
	
	    return true;
	  }
	
	  /**
	   * Sends a HELO/EHLO command.
	   * @access private
	   * @return bool
	   */
	  private function SendHello($hello, $host) {
	    fputs($this->smtp_conn, $hello . " " . $host . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($this->do_debug >= 2) {
	      echo "SMTP -> FROM SERVER: " . $rply . $this->CRLF . '<br />';
	    }
	
	    if($code != 250) {
	      $this->error =
	        array("error" => $hello . " not accepted from server",
	              "smtp_code" => $code,
	              "smtp_msg" => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	
	    $this->helo_rply = $rply;
	
	    return true;
	  }
	
	  /**
	   * Starts a mail transaction from the email address specified in
	   * $from. Returns true if successful or false otherwise. If True
	   * the mail transaction is started and then one or more Recipient
	   * commands may be called followed by a Data command.
	   *
	   * Implements rfc 821: MAIL <SP> FROM:<reverse-path> <CRLF>
	   *
	   * SMTP CODE SUCCESS: 250
	   * SMTP CODE SUCCESS: 552,451,452
	   * SMTP CODE SUCCESS: 500,501,421
	   * @access public
	   * @return bool
	   */
	  public function Mail($from) {
	    $this->error = null; // so no confusion is caused
	
	    if(!$this->connected()) {
	      $this->error = array(
	              "error" => "Called Mail() without being connected");
	      return false;
	    }
	
	    $useVerp = ($this->do_verp ? "XVERP" : "");
	    fputs($this->smtp_conn,"MAIL FROM:<" . $from . ">" . $useVerp . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($this->do_debug >= 2) {
	      echo "SMTP -> FROM SERVER:" . $rply . $this->CRLF . '<br />';
	    }
	
	    if($code != 250) {
	      $this->error =
	        array("error" => "MAIL not accepted from server",
	              "smtp_code" => $code,
	              "smtp_msg" => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	    return true;
	  }
	
	  /**
	   * Sends the quit command to the server and then closes the socket
	   * if there is no error or the $close_on_error argument is true.
	   *
	   * Implements from rfc 821: QUIT <CRLF>
	   *
	   * SMTP CODE SUCCESS: 221
	   * SMTP CODE ERROR  : 500
	   * @access public
	   * @return bool
	   */
	  public function Quit($close_on_error = true) {
	    $this->error = null; // so there is no confusion
	
	    if(!$this->connected()) {
	      $this->error = array(
	              "error" => "Called Quit() without being connected");
	      return false;
	    }
	
	    // send the quit command to the server
	    fputs($this->smtp_conn,"quit" . $this->CRLF);
	
	    // get any good-bye messages
	    $byemsg = $this->get_lines();
	
	    if($this->do_debug >= 2) {
	      echo "SMTP -> FROM SERVER:" . $byemsg . $this->CRLF . '<br />';
	    }
	
	    $rval = true;
	    $e = null;
	
	    $code = substr($byemsg,0,3);
	    if($code != 221) {
	      // use e as a tmp var cause Close will overwrite $this->error
	      $e = array("error" => "SMTP server rejected quit command",
	                 "smtp_code" => $code,
	                 "smtp_rply" => substr($byemsg,4));
	      $rval = false;
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $e["error"] . ": " . $byemsg . $this->CRLF . '<br />';
	      }
	    }
	
	    if(empty($e) || $close_on_error) {
	      $this->Close();
	    }
	
	    return $rval;
	  }
	
	  /**
	   * Sends the command RCPT to the SMTP server with the TO: argument of $to.
	   * Returns true if the recipient was accepted false if it was rejected.
	   *
	   * Implements from rfc 821: RCPT <SP> TO:<forward-path> <CRLF>
	   *
	   * SMTP CODE SUCCESS: 250,251
	   * SMTP CODE FAILURE: 550,551,552,553,450,451,452
	   * SMTP CODE ERROR  : 500,501,503,421
	   * @access public
	   * @return bool
	   */
	  public function Recipient($to) {
	    $this->error = null; // so no confusion is caused
	
	    if(!$this->connected()) {
	      $this->error = array(
	              "error" => "Called Recipient() without being connected");
	      return false;
	    }
	
	    fputs($this->smtp_conn,"RCPT TO:<" . $to . ">" . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($this->do_debug >= 2) {
	      echo "SMTP -> FROM SERVER:" . $rply . $this->CRLF . '<br />';
	    }
	
	    if($code != 250 && $code != 251) {
	      $this->error =
	        array("error" => "RCPT not accepted from server",
	              "smtp_code" => $code,
	              "smtp_msg" => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	    return true;
	  }
	
	  /**
	   * Sends the RSET command to abort and transaction that is
	   * currently in progress. Returns true if successful false
	   * otherwise.
	   *
	   * Implements rfc 821: RSET <CRLF>
	   *
	   * SMTP CODE SUCCESS: 250
	   * SMTP CODE ERROR  : 500,501,504,421
	   * @access public
	   * @return bool
	   */
	  public function Reset() {
	    $this->error = null; // so no confusion is caused
	
	    if(!$this->connected()) {
	      $this->error = array(
	              "error" => "Called Reset() without being connected");
	      return false;
	    }
	
	    fputs($this->smtp_conn,"RSET" . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($this->do_debug >= 2) {
	      echo "SMTP -> FROM SERVER:" . $rply . $this->CRLF . '<br />';
	    }
	
	    if($code != 250) {
	      $this->error =
	        array("error" => "RSET failed",
	              "smtp_code" => $code,
	              "smtp_msg" => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	
	    return true;
	  }
	
	  /**
	   * Starts a mail transaction from the email address specified in
	   * $from. Returns true if successful or false otherwise. If True
	   * the mail transaction is started and then one or more Recipient
	   * commands may be called followed by a Data command. This command
	   * will send the message to the users terminal if they are logged
	   * in and send them an email.
	   *
	   * Implements rfc 821: SAML <SP> FROM:<reverse-path> <CRLF>
	   *
	   * SMTP CODE SUCCESS: 250
	   * SMTP CODE SUCCESS: 552,451,452
	   * SMTP CODE SUCCESS: 500,501,502,421
	   * @access public
	   * @return bool
	   */
	  public function SendAndMail($from) {
	    $this->error = null; // so no confusion is caused
	
	    if(!$this->connected()) {
	      $this->error = array(
	          "error" => "Called SendAndMail() without being connected");
	      return false;
	    }
	
	    fputs($this->smtp_conn,"SAML FROM:" . $from . $this->CRLF);
	
	    $rply = $this->get_lines();
	    $code = substr($rply,0,3);
	
	    if($this->do_debug >= 2) {
	      echo "SMTP -> FROM SERVER:" . $rply . $this->CRLF . '<br />';
	    }
	
	    if($code != 250) {
	      $this->error =
	        array("error" => "SAML not accepted from server",
	              "smtp_code" => $code,
	              "smtp_msg" => substr($rply,4));
	      if($this->do_debug >= 1) {
	        echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF . '<br />';
	      }
	      return false;
	    }
	    return true;
	  }
	
	  /**
	   * This is an optional command for SMTP that this class does not
	   * support. This method is here to make the RFC821 Definition
	   * complete for this class and __may__ be implimented in the future
	   *
	   * Implements from rfc 821: TURN <CRLF>
	   *
	   * SMTP CODE SUCCESS: 250
	   * SMTP CODE FAILURE: 502
	   * SMTP CODE ERROR  : 500, 503
	   * @access public
	   * @return bool
	   */
	  public function Turn() {
	    $this->error = array("error" => "This method, TURN, of the SMTP ".
	                                    "is not implemented");
	    if($this->do_debug >= 1) {
	      echo "SMTP -> NOTICE: " . $this->error["error"] . $this->CRLF . '<br />';
	    }
	    return false;
	  }
	
	  /**
	  * Get the current error
	  * @access public
	  * @return array
	  */
	  public function getError() {
	    return $this->error;
	  }
	
	  /////////////////////////////////////////////////
	  // INTERNAL FUNCTIONS
	  /////////////////////////////////////////////////
	
	  /**
	   * Read in as many lines as possible
	   * either before eof or socket timeout occurs on the operation.
	   * With SMTP we can tell if we have more lines to read if the
	   * 4th character is '-' symbol. If it is a space then we don't
	   * need to read anything else.
	   * @access private
	   * @return string
	   */
	  private function get_lines() {
	    $data = "";
	    while($str = @fgets($this->smtp_conn,515)) {
	      if($this->do_debug >= 4) {
	        echo "SMTP -> get_lines(): \$data was \"$data\"" . $this->CRLF . '<br />';
	        echo "SMTP -> get_lines(): \$str is \"$str\"" . $this->CRLF . '<br />';
	      }
	      $data .= $str;
	      if($this->do_debug >= 4) {
	        echo "SMTP -> get_lines(): \$data is \"$data\"" . $this->CRLF . '<br />';
	      }
	      // if 4th character is a space, we are done reading, break the loop
	      if(substr($str,3,1) == " ") { break; }
	    }
	    return $data;
	  }
  }